Perhaps you should try some spelling variations:
thuat sach » thuat lanh, thuat san
danh diem » danh dien, dinh diem, dac diem
dau tren » dau tien, dat tren, dau tieng
diem dau » diem cau, diem du, dem dau
hieu van » hieu va, thien van, lieu va
toc tay » toc thai
te sach » toc sach
nang ma » tang ma, sang ma, nang cao
van cac » van hac, van cau, van bac
toc ta » toc thai
ma hoi » mai hoi, xa hoi, ma hoa

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: ((te sach) or (thuat sach)) ky nang ma hoi. hieu van cac ((toc ta) OR (toc tay)) danh diem dau tren~.
• If you are trying to use Boolean operators, they must be ALL CAPS: ((te sach) OR (thuat sach)) ky nang ma hoi. hieu van cac ((toc ta) OR (toc tay)) danh diem dau tren.
• The words AND, OR and NOT may confuse the search; try adding quotes: "((te sach) or (thuat sach)) ky nang ma hoi. hieu van cac ((toc ta) OR (toc tay)) danh diem dau tren".
• Adding a wildcard symbol may retrieve word variants: ((te sach) or (thuat sach)) ky nang ma hoi. hieu van cac ((toc ta) OR (toc tay)) danh diem dau tren*.